Yes, this is a real and common risk. Agencies that build complex custom workflows, serverless functions, or API-based integrations without proper documentation and training leave clients with a system they cannot troubleshoot, modify, or extend on their own.
The risk is highest with custom code. There is a meaningful difference between HubSpot configuration (properties, workflows, dashboards) and custom development (serverless functions, custom API endpoints, React-based modules). Configuration is manageable by trained internal teams. Custom development requires ongoing technical expertise. The mitigation is choosing a partner that designs for enablement rather than dependency. That means role-based training, documentation packages (including field mappings, workflow inventories, and runbooks), and an assigned internal champion who learns the system deeply enough to manage it post-launch. Lean Labs addresses this by guaranteeing one-on-one training and 90-day ongoing support as part of its implementation projects, with the explicit goal of full team adoption. The questions to ask before signing: What documentation do we receive at project close? Who trains our team, and on what? What does the handoff process look like? If the partner cannot describe a clear knowledge transfer plan, the dependency risk is high.